New SWD Connector

One of the generic changes I have considered for some time is to replace my 2×5 pin SWD connector with a 1×5 pin Micro JST connector. These connectors use 1.27 pitch and you get plenty of ready made cables. Firstly I only use 1×5 pin anyway and usually find other solutions for debug UART. But, most important is that connecting the adaptor directly to the board is not always convenient in tight places. A JST connector with a cable will fit more smoothly and allow me more freedom.


The picture don’t really show how small these connectors are, but you find plenty of them searching for “micro jst”. I plan to modify the existing adaptor and use this cable between the adaptor and the PCB Board so that I don’t need to adapt it directly.

Pin layout is still the same except for the New 3.3V:

  • 3.3V (new on 6-pin)
  • NRST
  • GND
  • BOOT

I assume I have to make it 6-pin and add 3.3V as I want Reset and Boot jumpers/switches on the next adapter board. Basically I don’t really need to do anything as I can use this directly as a drop in replacement on the existing Connectors (1×5-pin).

Also, I often have lack of connector space on my designs, so I am tempted to use these several places where the connector size is an issue!

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